Two landmark clinical trials, Look AHEAD (Action for Health in Diabetes) and the Diabetes Prevention Program (DPP) have demonstrated that an intensive lifestyle intervention resulting in modest weight loss and increased physical activity can improve control of cardiometabolic risk factors and is likely to be a cost-effective use of resources for persons with dysglycemia (i.e. either diabetes or pre-diabetes). Although these conditions together affect over 80 million Americans, the Look AHEAD and DPP lifestyle interventions were not designed for delivery on a population scale. Primary care settings are well suited to identify, activate, and provide follow-up for adults with dysglycemia, but these settings are far less equipped than many community organizations to offer intensive behavioral interventions to a large and growing population. We have collaborated with the leadership of primary care clinics and the YMCA for over 6 years to design and pre-test a practical model to identify, counsel, and refer high-risk primary care patients for access to a group-based adaptation of the DPP lifestyle intervention in YMCA facilities. Preliminary data from two R34 planning grants provides strong support that the YMCA can implement a group-based DPP lifestyle intervention and achieve weight loss that is comparable to the original DPP model (-6.0%;95% CI -4.6 to -7.4%). In parallel to these findings, emerging results from Look AHEAD have demonstrated that similar weight reduction and meaningful improvements in cardiometabolic risk factors are achievable and safe in adults with type 2 diabetes who are offered a very similar intensive lifestyle intervention. As a result, we propose this new study to evaluate the costs and effectiveness of a collaborative approach to identify adults with dysglycemia (either diabetes OR pre-diabetes) in primary care settings and to provide access to a group-based intensive lifestyle intervention at community-based YMCAs that has been carefully adapted from both the DPP and Look AHEAD approaches. This intervention will include more structured linkages between primary care and the community program to help clinicians improve the management of cardiometabolic risk in these patients. The study will involve 8 primary care clinics and 6 YMCA sites and will employ a mix of qualitative and quantitative methods, over a 2-year intervention period, to evaluate the reach, adoption, implementation, and maintenance of intervention activities, and to mount a practical randomized effectiveness trial to evaluate the effect of this partnered intervention to achieve and maintain modest weight loss and improved cardiometabolic risk in adult primary care patients with dysglycemia. Should our study find this partnered intervention strategy to be effective and sustainable, the results will be pivotal to the timely and efficient dissemination of this approach as a nationwide model to address the diabetes epidemic. PUBLIC HEALTH RELEVANCE: The proposed study is designed to evaluate the costs and effectiveness of a scalable model to translate the Look AHEAD (Action for Health in Diabetes) and DPP lifestyle intervention strategies for population- level delivery using partnerships between primary care and community-based YMCA settings. Should our study find this partnered intervention model to be effective and sustainable, the results will be pivotal to the timely and efficient dissemination of this approach as a nationwide model for improving cardiometabolic risk for over 24 million Americans with diabetes and 60 million with pre-diabetes.